Dyeing



Patented Dec. 22, 1931 I UNITED STATES PATENT OFFICE GEORGE srrzucm or NOTTINGHAM, ENGLAND. .sssrcnon. BY mun assrcmmn'rs, 1 To ssm'rmrc rms'rrcs comm, Incoaromrnn, or new YORK, N. Y, A con.-

POEATION' PF DELAWARE DYEIZNG- m5 Drawing. Application tiled June 21, 1928, Serial No. 287,851, and in Great Britain June 24, 1827.

i This invention relates to an improvement in the art of dyeing. The invention consists in the various improvements hereafter described and claimed. According to the present invention in its preferred form, I first impregnate textile yarns or fabrics or other materials such as furs, wool or leather with a soluble condensation product of urea or preferably thio-urea with formaldehyde, hereafter termed semi-condensate, and I then treat the impregnated material by dyeing or printing.

The semi-condensate may be prepared by known processes, such as those for the manufacture of condensation products to the stage preceding gelatinization described in British Patents (Pollak) #157,416, #171,094, #181,014, #187,605, #193,420, #201,906, #206,512, #213,567 and #248,729.

The semi-condensate is employed in the state of dilution suitable for the particular purposes intended, as for example where a slight effect is required, 2%% by weight of.

condensate in water.

The semi-condensate may be employed either coloured (by means of dyes, etc.) or clear.

The material to be dyed may be impregnated with theIsemi-condensate uniformly or superficially to produce ingrain and all-over efiects, or may be impregnated to produce pattern effects.

The impregnated material may be dyed before or after drying out the semi-condensate, but preferably drying precedes dyeing and/or printing so as to cause further con: densation of the semi-condensate and thus to convert it into an insoluble condensate in known manner.

It is found that according to the dyestuffs I and colours, mordants and the like used, and

the nature of the fibres of the impregnated material, such material exhibits various ailinities and resistances and degrees of affinity and resistance for the dyestuffs, colours, etc., e. g. the semi-condensate may act as an activator of absorption, as a resist, or it may selectively absorb this or that element of a dye or mordant, or one or more v the grey, one is uniformly impregnated with semi-condensate and dried out, the other is left untreated; both are simultaneously immersed in a dye-bath of a suitable direct violet dyestuff and dyed; on simultaneous withdrawal 0f the cloths, the impregnated cloth will be found to have abstracted much more of the dye than the untreated cloth and to be of a deeper shade of heliotrope.

(b) A plain cotton cloth in the grey is 1 pattern printed with semi-condensate, dried out and dyed in the same bath as in (a); on withdrawal, the pattern will be presented in a deeper shade of heliotrope than the ground. I

(0) A similar cotton cloth is similarly pattern printed, dried out and dyed in a bath of direct brown M (colour index No. 420); on withdrawal, the pattern will be presented faintly tinged with colour on a deeper coloured ground.

(03) A similar cotton cloth is similarly pattern printed, dried out and dyed in a bath of a suitable basic blue dyestuff; on withdrawal, the pattern will be presented faintly tinged with colour on a deeper coloured ground. a

The colours of the dyed fabric may be varied by substituting coloured condensate for clear and semi-condensate, when, in consequence of the semi-condensate abstracting additional colour from the dye-bath, the final colour of the semi-condensate may be altered.

Impregnated material may also be printed with suitable dyes either in self-colour, or-

I declare that what I claim" is 1. The process of colouring material whlch consists in ap lyin thereto 1n selected areas a soluble semi-con ensate of thio-urea with formaldehyde and then applying a dyestufi thereto.

2. The process of colouring material which consists in applying thereto a soluble semicondensate of thio-urea and formaldehyde, rendering said condensate insoluble and applying a dyestufi' to the material.

3. The process of colourin material which consists in applyin thereto 1n selected areas a soluble semi-con ensate produced by reactin one of the group consisting of urea and thlo-urea with formaldehyde and then applying a dyestufl' thereto.

4. The process of colouring material which consists in applying thereto a soluble semicondensate produced by reacting one of the group consisting of urea and thio-urea and formaldehyde, making said condensate insoluble and applying a dyestufl' to the material.

In witness whereof, I have hereunto signed my name this llth'day of June, 1928.

GEORGE SPENCER. 

